列表中的元素求和

下面是我的代码，我需要对列表中未定义数量的元素求和。如何做到这一点？

l = raw_input()
l = l.split(' ')
l.pop(0)

我的输入: 3 5 4 9 输入后，我通过 l.pop(0)删除第一个元素。 在 .split(' ')之后，我的列表是 ['5', '4', '9']，我需要对列表中的所有元素求和。

在这种情况下，和是18。请注意，没有定义元素的数量。

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最佳答案

You can sum numbers in a list simply with the sum() built-in:

sum(your_list)

It will sum as many number items as you have. Example:

my_list = range(10, 17)
my_list
[10, 11, 12, 13, 14, 15, 16]


sum(my_list)
91

For your specific case:

对于您的数据，首先将数字转换为int，然后对数字求和:

data = ['5', '4', '9']


sum(int(i) for i in data)
18

This will work for undefined number of elements in your list (as long as they are "numbers")

Thanks for @senderle's comment re conversion in case the data is in string format.

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Python iterable can be summed like so - [sum(range(10)[1:])] . This sums all elements from the list except the first element.

>>> atuple = (1,2,3,4,5)
>>> sum(atuple)
15
>>> alist = [1,2,3,4,5]
>>> sum(alist)
15
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You can use sum to sum the elements of a list, however if your list is coming from raw_input, you probably want to convert the items to int or float first:

l = raw_input().split(' ')
sum(map(int, l))
小开 
>>> l = raw_input()
1 2 3 4 5 6 7 8 9 10
>>> l = l.split()
>>> l.pop(0)
'1'
>>> sum(map(int, l)) #or simply sum(int(x) for x in l) , you've to convert the elements to integer first, before applying sum()
54
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You can use map function and pythons inbuilt sum() function. It simplifies the solution. And reduces the complexity.
a=map(int,raw_input().split())
sum(a)
Done!

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def sumoflist(l):
total = 0
for i in l:
total +=i
return total
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You can also use reduce method:

>>> myList = [3, 5, 4, 9]
>>> myTotal = reduce(lambda x,y: x+y, myList)
>>> myTotal
21

Furthermore, you can modify the lambda function to do other operations on your list.


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